1. Field of the Invention
The present invention relates generally to a mobile telephone terminal, and in particular, to a camera lens assembly for a foldable mobile telephone terminal rotatably coupled onto a center hinge arm of the terminal.
2. Description of the Related Art
A mobile telephone terminal is a portable mobile station that provides radio communication services to its subscriber while wirelessly communicating with its base station. Rapid development in the field of information and telecommunication business has made it possible for mobile users to use a variety of functions, and many types of mobile phones are available on the market. These mobile telephone terminals are generally classified into three or more types of terminals, such as a bar-type terminal, a flip-type terminal with a flip cover, and a foldable terminal with a folder adapted to be open and closed about a main body at a given angle.
In recent years, one of the most favorite trends in the marketplace has been mobile terminals that are designed to serve various additional functions as well as its basic wireless telephoning function for speaking on the phone with a called party. Such additional functions may include, for example, e-mail or data communication service, Internet game service, short message service, etc. Further, with a new generation of mobile communication system such as CDMA 1×EVDO having been actively introduced to the market, most of those up-to-date mobile terminals tend to extend their service capability to include image communications between mobile subscribers, moving picture service, etc. As such, the extension in service area of mobile phones to include image communications or moving picture service using mobile phones allows a camera lens to be added as one of the essential components in mobile phones recently on the market.
Such camera lenses adapted for mobile phones generally include two types of lenses, depending upon the configuration of the mobile phones, such as a fixed type camera lens having an exposed window formed through a periphery of a mobile phone, and a rotation type camera lens rotatably arranged onto a hinge axis of a folder type terminal.
FIG. 1 is a perspective view illustrating a conventional foldable mobile terminal 100 applied to the present invention with its sub-body unfolded, which terminal includes a main body 101 and a folder 102, the folder being rotatably coupled to the main body by means of a hinge assembly to allow a user to open or close the folder with respect to the main body 101 as desired. As seen in FIG. 1, the mobile terminal 100 has a pair of side hinge arms 115 and a center hinge arm 125 for coupling the main body 101 to the folder 102, and a lens housing 201 is arranged in an opening 127 (shown in FIG. 2) formed through the center hinge arm 125.
The main body 101 is configured such that a keypad assembly 111 and a microphone 113 are arranged on a front surface of the main body, and the two side hinge arms 115 each are positioned in the uppermost ends opposing each other. The folder 102 is configured such that the center hinge arm 125 is disposed in the lower end for coupling between the two side hinge arms 115, and a display unit 121 and a speaker 123 are arranged on a front surface facing the main body 101. As the center hinge arm 125 is coupled in between the two side hinge arms 115, the folder 102 is allowed to rotate about a hinge axis (A) extending through the side hinge arms 115 for opening or closure of the folder with respect to the main body 101. In the meantime, through the center hinge arm 125 is formed an opening or aperture 127 for receiving a lens housing 201 in a direction intersecting the hinge axis (A).
FIG. 2 is an exploded perspective view for illustrating the disassembled configuration of a camera lens assembly of a mobile communication terminal according to the prior art, and FIG. 3 is an exploded perspective view for illustrating in further detail the camera lens assembly shown in FIG. 2. As shown in FIGS. 2 and 3, the camera lens assembly of a mobile terminal according to the prior art is rotatably coupled to for the center hinge arm 125 in the opening 127 formed through the center hinge arm 125 of the folder 102, both ends of the camera lens assembly being supported by a hinge dummy 203 and a hinge module 209. The camera lens assembly is provided with cylindrical lens housing 201 in which a camera lens is installed. The cameral lens housing 201 has an exposed window 211 in its periphery and has a supporting recess 213 in its one end, and a housing holder 215, as shown in FIG. 3, is coupled with the other end. The housing holder 215 may be of an annular plate shape, on one side of which a plurality of serration holes 219 are arranged at intervals of even distance along its circumferential direction. The housing holder 215 is fixed to the opposite end of the lens housing 201 by means of fasteners such as screws.
The hinge module 209 is accommodated in the center hinge arm 125 for generation of a rotating force to open or close the folder 102. The construction of this hinge module 209 is disclosed in further detail in a Korean Patent No. 296048 issued on May 7, 2001 to the same assignee as the present application, the content of which is incorporated herein by reference. Further, the hinge module 209 is provided with a supporting protrusion (not shown) for supporting the lens housing 201 so that the supporting protrusion extends to one end of the opening 127. The supporting protrusion may be accommodated within the hinge module 209 or a hinge bore 125b in which the hinge module 209 is received, which is adapted to extend to one end of the opening 127 so that it is rotatably coupled with supporting recess 213 in one end of the lens housing 201.
The other end of the lens housing 201 is supported by a hinge dummy 203, which is fixedly coupled to the side hinge arm 115 and also rotatably coupled with a rotation hole 125a in the center hinge arm 125, its end being adapted to support the other end of the lens housing 201. As such, the hinge dummy 203 is configured to provide a hinge coupling in between the main body 101 and folder 102 and to support the other side to provide a pivot axis for the lens housing 201.
The hinge dummy 203 cylinder shaped, with one side of which a cap-shaped pin holder 237 is coupled. The pin holder 237 is fastened to one end of the hinge dummy 203 using fastening means such as screws, and spring pins 235 are positioned inside the pin holder, in such a way that they appear and disappear, either outwardly or inwardly, in a direction towards the lens housing 201 facing the housing holder 215. The spring pins 235 functions to protrude through pin holder 237 with help of elastic force provided by a coil spring. When the lens housing is caused to rotate, the spring pins 235 move following the traces of the pinhole 219 in the housing holder 215. Thus, the spring pins 235 move following the traces formed by the serration holes 219, engaging each other to thereby provide its user with feeling of clicks.
It has been appreciated however, that a camera lens assembly in such a prior art mobile telephone terminal may have a significant disadvantage in that too much extra noise is generated in between a spring pin and a housing holder arranged in one end of the lens housing. Moreover, the vertical movement of a pin by means of a spring is sometimes not so smooth, which will hinder precise rotation of the lens housing.